Yes, I think wifi helps tourism because wifi allows tourists to use networks to locate information that is pertinent to their stay in a city or country. By allowing tourists to access such information, the city or country becomes a bit "smaller", and more catering. Thus, I see no reason that wifi would not help tourism.
With today's world, most people are hesitant to even take bottles with liquids on a plane. Even more are scared of people stealing things from their suitcases. If having liquid is suspicious on a plane, what about a giant Wi-Fi tower? If people can't have Wi-Fi, how will they keep in touch with friends and family? They can't exactly take a tower with them. If someone wants a vacation, they will most likely go to the spot with Wi-Fi.